243361 has 4 divisors (see below), whose sum is σ = 244372. Its totient is φ = 242352.

The previous prime is 243343. The next prime is 243367. The reversal of 243361 is 163342.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length, and also an emirpimes, since its reverse is a distinct semiprime: 163342 = 2 ⋅81671.

It can be written as a sum of positive squares in 2 ways, for example, as 57600 + 185761 = 240^2 + 431^2 .

It is a cyclic number.

It is not a de Polignac number, because 243361 - 2⁷ = 243233 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (243367) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 91 + ... + 703.

It is an arithmetic number, because the mean of its divisors is an integer number (61093).

2²⁴³³⁶¹ is an apocalyptic number.

It is an amenable number.

243361 is a deficient number, since it is larger than the sum of its proper divisors (1011).

243361 is an equidigital number, since it uses as much as digits as its factorization.

243361 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1010.

The product of its digits is 432, while the sum is 19.

The square root of 243361 is about 493.3163285358. The cubic root of 243361 is about 62.4334010585.

Subtracting from 243361 its sum of digits (19), we obtain a palindrome (243342).

The spelling of 243361 in words is "two hundred forty-three thousand, three hundred sixty-one".